References of "Lemort, Vincent"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailORCmKit: an open-source library for organic Rankine cycle modelling and analysis
Dickes, Rémi ULiege; Ziviani, Davide; van den Broek, Martjin et al

in Proceedings of ECOS 2016 (2016, June 20)

As for many other technologies, modelling and simulation of organic Rankine cycles (ORCs) are crucial for design, optimization and control purposes. However, model development is often time consuming and ... [more ▼]

As for many other technologies, modelling and simulation of organic Rankine cycles (ORCs) are crucial for design, optimization and control purposes. However, model development is often time consuming and the scientific community lacks of open-access tools to study ORC systems. For these reasons, researchers from the universities of Liège and Ghent in Belgium gathered their knowledge and created “ORC modelling Kit” (ORCmKit), an open-source library dedicated to the steady-state simulation and analysis of organic Rankine cycles. Both component-level and cycle-level models are provided and different ORC architectures can be simulated. For each of the main component of ORC systems, different models are available with increasing complexity which allows a wide range of modelling possibilities. In order to remain general and accessible to as many people as possible, three widely used programming languages are covered within ORCmKit, i.e. Matlab, Python and EES (Engineering Equation Solver). Besides source codes, ORCmKit also includes calibration tools for empirical and semi-empirical models as well as a complete documentation for ease of use. [less ▲]

Detailed reference viewed: 312 (12 ULiège)
Full Text
Peer Reviewed
See detailOrganic Rankine cycle modelling and the ORCmKit library: analysis of R1234ze(Z) as drop-in replacement of R245fa for low-grade waste heat recovery
Ziviani, Davide; Dickes, Rémi ULiege; Quoilin, Sylvain ULiege et al

in Proceedings of ECOS 2016 (2016, June 20)

Due to the wide interest in organic Rankine cycles (ORCs) as a sustainable technology and the importance of numerical analyses and optimization procedures while considering such systems, we created a ... [more ▼]

Due to the wide interest in organic Rankine cycles (ORCs) as a sustainable technology and the importance of numerical analyses and optimization procedures while considering such systems, we created a dedicated open-source library named “ORC modelling Kit” (ORCmKit). The comprehensive library includes single com-ponents and overall models for subcritical, transcritical and supercritical ORCs. Three main programming environments are currently supported: Matlab, Python and EES (Engineering Equation Solver). A detailed steady-state cycle model of a small-scale regenerative ORC with a single-screw expander is used to evalu-ate the performance influence of R1234ze(Z) as a drop-in replacement of R245fa currently used in the instal-lation. The ORC system is used to recover low-grade waste heat with a temperature range between 90°C and 120°C. A thermal oil heater is used to simulate the heat source. A parametric study is carried out to in-vestigate the performance of the system throughout the range of interest in order to optimize the ORC with R1234ze(Z). [less ▲]

Detailed reference viewed: 123 (7 ULiège)
Full Text
Peer Reviewed
See detailSteady-state and dynamic modelling of a 1 MWel commercial waste heat recovery ORC power plant
Andritsos, George; Desideri, Adriano ULiege; Gantiez, Clement et al

in Steady-state and dynamic modelling of a 1 MWel commercial waste heat recovery ORC power plant (2016, June 19)

ORC power systems have been proven to be a mature technology for low quality waste heat recovery applications. ORC units stand out for their simple structure, reliability and cost- effectiveness. The non ... [more ▼]

ORC power systems have been proven to be a mature technology for low quality waste heat recovery applications. ORC units stand out for their simple structure, reliability and cost- effectiveness. The non-constant nature of the energy source requires the ORC power unit to be flexible. Dynamic modelling can be adopted to evaluate and optimize the response time of a system in case of transient conditions, to develop and test control strategies, to support the tuning of the controller and to support maintenance. In this work the dynamic model of a 1 MWel commercial ORC unit is presented. The dynamic model is developed based on the ThermoCycle Modelica library. The different component model are validated in steady-state against 21 measurements points. The dynamic model of the whole power unit is then developed connecting the validated component models. Different modelling approaches of various complexity are implemented to model the heat exchangers of the power system. The performance of the developed heat exchanger (HX) models are tested by running different transient simulations. The results allow identifying benefits and limitations of the tested HX modelling approaches. [less ▲]

Detailed reference viewed: 43 (4 ULiège)
Full Text
Peer Reviewed
See detailModélisation d'une climatisation automobile multi-évaporateurs
Gillet, Thomas ULiege; Rullière, Romuald; Haberschill, Philippe et al

Poster (2016, June 02)

La modélisation d’une climatisation automobile multi-évaporateurs, composées de deux évaporateurs et d’un refroidisseur de fluide secondaire, a été réalisée à l’aide du logiciel LMS Imagine.Lab Amesim® 1D ... [more ▼]

La modélisation d’une climatisation automobile multi-évaporateurs, composées de deux évaporateurs et d’un refroidisseur de fluide secondaire, a été réalisée à l’aide du logiciel LMS Imagine.Lab Amesim® 1D. Dans le but d’étudier le comportement de la boucle, des perturbations sous la forme d’échelon ont été simulées sur un point de fonctionnement à moyenne et haute charge. L’impact de ces perturbations sur la stabilité de la température d’air soufflé est analysé pour deux types de détendeur. Les premiers résultats montrent que les détendeurs thermostatiques peuvent engendrer des instabilités. [less ▲]

Detailed reference viewed: 29 (4 ULiège)
Full Text
Peer Reviewed
See detailPerformance evaluation of an Organic Rankine Cycle (ORC) connected to two-phase closed thermosyphons
Le, Van Long ULiege; Declaye, Sébastien ULiege; Dumas, Xavier et al

in PROCEEDINGS OF ECOS 2016 (2016, June)

This paper aims at evaluating the performance of a waste heat-to-power plant using an organic Rankine cycle (ORC) connected to two-phase closed thermosyphons (or gravity-assisted heat pipes or wickless ... [more ▼]

This paper aims at evaluating the performance of a waste heat-to-power plant using an organic Rankine cycle (ORC) connected to two-phase closed thermosyphons (or gravity-assisted heat pipes or wickless heat pipes). The heat exchanger, made up of two-phase closed thermosyphons, is used for transferring heat from exhaust stream to ORC working fluid. In practice, a hot oil loop or a pressurized hot water loop or a saturated steam loop or even a direct evaporator is often used to transfer heat from heat source to ORC system. However, installing a heat exchanger directly in the hot gas paths of ORC system evokes the concerns for the flammability and/or toxicity of organic working fluids especially when the heat source has a relative high temperature. Also the use of an intermediate heat carrier loop such as thermal oil or saturated steam or pressurized water loop is relatively expensive and involves installation of relatively heavy components. A priori, the use of two-phase closed thermosyphons for capturing and transferring heat from a waste heat source to organic working fluid is less expensive than the use of an intermediate heat transfer loop and eliminates safety concerns as in the case of direct installation of an ORC evaporator in the hot gas paths. [less ▲]

Detailed reference viewed: 102 (37 ULiège)
Full Text
Peer Reviewed
See detailDirect control service from residential heat pump aggregation with specified payback
Georges, Emeline ULiege; Cornélusse, Bertrand ULiege; Ernst, Damien ULiege et al

in Proceedings of the 19th Power Systems Computation Conference (PSCC) (2016, June)

This paper addresses the problem of an aggregator controlling residential heat pumps to offer a direct control flexibility service. The service is defined by a 15 minute power modulation, upward or ... [more ▼]

This paper addresses the problem of an aggregator controlling residential heat pumps to offer a direct control flexibility service. The service is defined by a 15 minute power modulation, upward or downward, followed by a payback of one hour and 15 minutes. The service modulation is relative to an optimized baseline that minimizes the energy costs. The potential amount of modulable power and the payback effect are computed by solving mixed integer linear problems. Within these problems, the building thermal behavior is modeled by an equivalent thermal network made of resistances and lumped capacitances whose parameters are identified from validated models. Simulations are performed on 100 freestanding houses. For an average 4.3 kW heat pump, results show a potential of 1.2 kW upward modulation with a payback of 600 Wh and 150 Wh of overconsumption. A downward modulation of 500 W per house can be achieved with a payback of 420 Wh and 120 Wh of overconsumption. [less ▲]

Detailed reference viewed: 194 (35 ULiège)
Full Text
Peer Reviewed
See detailTowards nzeb goal for newly built office buildings in Europe using high temperature cooling.
Randaxhe, François ULiege; Lemort, Vincent ULiege; Lebrun, Jean ULiege

Conference (2016, May 24)

In the design phase of a building, many HVAC systems options are available to satisfy the basic requirements related to its use. The design engineer is responsible for considering various systems and ... [more ▼]

In the design phase of a building, many HVAC systems options are available to satisfy the basic requirements related to its use. The design engineer is responsible for considering various systems and recommending a system that will meet the project goals and perform as desired. In addition, high efficiency requirements are imposed to the HVAC equipments through strong regional regulation such as the Energy Performance of Buildings Directive which requires minimum efficiency of HVAC equipments in the market. In reaction, major improvements have been made by manufacturers to improve the performance of their systems and meet all these criteria. With the nearly zero energy goal for all newly constructed buildings in Europe after 2020, it seems very likely that the design of the future building should rely on today’s technology to meet these targets. The integration of High Temperature Cooling in buildings can bring a fresh perspective in this context. The study presents the sensitivity analysis of a primary system to chilled water supply temperature for a water cooled chiller with a cooling tower and a free-chilling heat exchanger. It allows a proper assessment of the impact of the chilled water temperature on the primary system performance. [less ▲]

Detailed reference viewed: 18 (2 ULiège)
Full Text
Peer Reviewed
See detailDescription of a Modelica-based thermal building model integrating multi-zone airflows calculation
Ransy, Frédéric ULiege; Gendebien, Samuel ULiege; Lemort, Vincent ULiege

Conference (2016, May 23)

Nowadays, in newly built housings, energy losses due to the ventilation can represent up to 50 % of the total building energy consumption. As a result, heat recovery ventilation units are widely used in ... [more ▼]

Nowadays, in newly built housings, energy losses due to the ventilation can represent up to 50 % of the total building energy consumption. As a result, heat recovery ventilation units are widely used in order to save primary energy and different control strategies for ventilation systems are investigated. For instance, demand control ventilation sounds like a promising solution to decrease the energy impact of the ventilation system in the residential sector. An accurate building model integrating the influence of ventilation (so called thermo-aeraulic building model) is necessary in order to investigate the control and the impact of the ventilation system on a yearly basis. The aim of the present paper consists in a description of a combined multi-zone airflow network model and thermal building model implemented in the Modelica language. The thermal model is a simplified dynamic model using equivalent thermal resistance and capacity. The airflow network is based on the traditional electrical circuit analogy. The model can be used for ventilation systems design, infiltration rate calculation, inside air quality calculation, energy consumption calculation, etc. The first part of the paper details the multi-zone thermal building model. The results obtained from the model are compared to experimental in situ results collected in the typical single family house test facilities. Those experimental results have been obtained in the frame of the IEA-EBC Annex 58. The second part of the paper introduces the multi-zone airflow network building model. Obtained model results are compared with the results provided by a typical multizone airflow analysis software, for a simple three zones test case. The third part of the paper describes the coupling between both thermal and airflow models. The different numerical problems encountered are described and solutions are discussed. [less ▲]

Detailed reference viewed: 96 (22 ULiège)
Full Text
See detailAnalysis of the flexibility of Belgian residential buildings equipped with Heat Pumps and Thermal Energy Storages
Georges, Emeline ULiege; Garsoux, Pierre; Masy, Gabrielle et al

in Proceedings of CLIMA2016 Conference (2016, May)

Detailed reference viewed: 56 (8 ULiège)
Full Text
Peer Reviewed
See detailEnergy Reduction in Public Building Stock: Assessing the Impact of Control Strategy over Expected Energy Savings and Indoor Comfort Level
Ruiz Flores, Roberto ULiege; D’Antoni, Matteo; Lemort, Vincent ULiege

in CLIMA 2016 - proceedings of the 12th REHVA World Congress: volume 1. Aalborg: Aalborg University, Department of Civil Engineering. (2016, May)

In the framework of EU FP7 BRICKER project, the renovation of public owned nonresidential buildings is addressed through the installation of innovative passive and active technologies. The expected impact ... [more ▼]

In the framework of EU FP7 BRICKER project, the renovation of public owned nonresidential buildings is addressed through the installation of innovative passive and active technologies. The expected impact is a primary energy reduction of about 50% with respect to the existing scenario with a large replication potential under different European countries. In order to achieve such ambitious goal one issue that cannot be ignored is the effect of control strategy, not only over the resulting energy performance but also over the resulting indoor comfort conditions. In this paper, the actual control strategy implemented in the Belgian demo of Bricker project is introduced, compared against an ideal approach and accordingly optimized. The resulting proposed approach is then tested by means of numerical simulations over a base case scenario before renovation. The main conclusion of this work is the demonstration that control strategy of energy generation and distribution systems has to be revised whenever deep renovation of passive or active building technologies is undertaken. Contrarily to which, project renovation goals cannot be met. [less ▲]

Detailed reference viewed: 63 (9 ULiège)
Full Text
See detailIntroduction aux échangeurs de chaleur
Declaye, Sébastien ULiege; Gendebien, Samuel ULiege; Lemort, Vincent ULiege

Conference (2016, April 14)

Detailed reference viewed: 28 (4 ULiège)
Full Text
Peer Reviewed
See detailPerformance of a radial-inflow turbine integrated in an ORC system and designed for a WHR on truck application: An experimental comparison between R245fa and R1233zd
Guillaume, Ludovic ULiege; Legros, Arnaud ULiege; Desideri, Adriano ULiege et al

in Applied Energy (2016)

The goal of this study is to experimentally compare the performance of an Organic Rankine Cycle (ORC) system equipped with a radial-inflow turbine for two working fluids: R245fa and R1233zd. The radial ... [more ▼]

The goal of this study is to experimentally compare the performance of an Organic Rankine Cycle (ORC) system equipped with a radial-inflow turbine for two working fluids: R245fa and R1233zd. The radial- inflow turbine is a small-scale prototype designed to convert the waste heat from the exhaust gases of a truck combustion engine and was developed mainly using components of truck turbochargers. It is directly connected to a high-speed synchronous generator. The bearings system of the turbine and the generator have the innovative particularity to be respectively lubricated and cooled down by the working fluid so no additional lubricant or coolant is needed. The experimental comparison is carried out over a test-rig equipped with the radial turbine. The heat wasted by the truck through the exhaust gases is sim- ulated using an electric oil boiler coupled to the ORC loop. The electrical power supplied by the turbine, limited to a maximum of 3.5 kWel by the generator, is then dissipated in a load bank composed of truck fans while the condenser is cooled by a water loop. Measurements in steady-state are performed in order to evaluate the performance of the turbine-generator set when varying the pressure ratio, the rotational speed, the inlet temperature and the mass flow rate of the turbine and the lubrication flow rate of the bearings for various oil temperatures and mass flow rates. In order to identify the most suitable fluid for the Waste Heat Recovery (WHR) application, three comparison methods are proposed and discussed based on the measurements. Finally, because the turbine-generator set is the first oil-free prototype developed by the manufacturer, potential sources of improvements are discovered and discussed. [less ▲]

Detailed reference viewed: 55 (14 ULiège)
Full Text
Peer Reviewed
See detailExperimental comparison of organic fluids for low temperature ORC (organic Rankine cycle) systems for waste heat recovery applications
Desideri, Adriano ULiege; Gusev, Sergei; Van den Broek, Martijn et al

in Energy (2016), 97

This contribution experimentally evaluates and compares the performance of an ORC (organic Rankine cycle) system for stationary bottoming WHR (waste heat recovery) application operating with two different ... [more ▼]

This contribution experimentally evaluates and compares the performance of an ORC (organic Rankine cycle) system for stationary bottoming WHR (waste heat recovery) application operating with two different working fluids, SES36 and R245fa. The test rig is a regenerative cycle equipped with a single screw expander modified from a standard compressor characterized by a nominal shaft power of 11 kW. A total of 36 and 43 steady-state points are collected for SES36 and R245fa respectively, over a wide range of operating conditions by changing the expander rotational speed, the pump frequency and the cooling condenser flow rate. The performances of the ORC components are individually evaluated. A maximum expander isentropic efficiency of 60% is reached using SES36 at 3000 rpm, and a value of 52% is reached with R245fa at 3000 rpm. However, for a given pressure ratio the expander output power is higher with R245fa than with SES36. The overall performance of the ORC unit are investigated in terms of first and second law efficiencies and net output power for the two fluids. The results experimentally demonstrate the correlation between the working fluid critical temperature and the ORC unit working characteristics for low temperature waste heat recovery applications. Open experimental data are provided for both fluids. [less ▲]

Detailed reference viewed: 46 (12 ULiège)
Full Text
See detailResidential heat pumps as flexible loads for direct control service with constrained payback
Georges, Emeline ULiege; Cornélusse, Bertrand ULiege; Ernst, Damien ULiege et al

Conference (2016, January 26)

This paper addresses the problem of an aggregator controlling residential heat pumps to offer a direct control flexibility service. The service is defined by a 15 minute power modulation, upward or downward ... [more ▼]

This paper addresses the problem of an aggregator controlling residential heat pumps to offer a direct control flexibility service. The service is defined by a 15 minute power modulation, upward or downward, followed by a payback of one hour and 15 minutes. The service modulation is relative to an optimized baseline that minimizes the energy costs. The potential amount of modulable power and the payback effect are computed by solving mixed integer linear problems. Within these problems, the building thermal behavior is modeled by an equivalent thermal network made of resistances and lumped capacitances whose parameters are identified from validated models. Simulations are performed on 100 freestanding houses. For an average 4.3 kW heat pump, results show a potential of 1.2 kW upward modulation with a payback of 600 Wh and 150 Wh of overconsumption. A downward modulation of 500 W per house can be achieved with a payback of 420 Wh and 120 Wh of overconsumption. [less ▲]

Detailed reference viewed: 27 (4 ULiège)
Full Text
Peer Reviewed
See detailAbout the use of CO2 as tracer gas for identification of air renewal; combination with co-heating test
Andre, Philippe ULiege; Aparecida Silva; Davin, Elisabeth ULiege et al

in Heiselberg, Per Kvols (Ed.) CLIMA 2016 - Proceedings of the 12th REHVA World Congress : volume 5 (2016)

Three types of tracer gas test are, until now, mentioned in international standards: Injection at constant indoor concentration, injection at constant flow rate and transient injection followed by a ... [more ▼]

Three types of tracer gas test are, until now, mentioned in international standards: Injection at constant indoor concentration, injection at constant flow rate and transient injection followed by a recording of the decontamination curve. A fourth method is proposed in this paper: it is based on the same scenario as the third method, but with weighting of the mass of tracer gas (CO2) injected and integration of the curve of indoor concentration on the whole testing period. The concentration peak is used to identify the “effective” volume of the building zone considered; this volume, associated to the final concentration, is used to calculate the amount of CO2 remaining inside the zone at the end of the test. The total mass of renovation air is then deduced from the corresponding CO2 mass balance. The CO2 can be injected from a bottle or directly produced by combustion on site. In the latter case, the tracer gas method is combined with a co-heating test. It can be done, for example, with a current camping butane cooker: From the weighting of this device and continuous recording of air temperature, CO2 concentration and humidity ratio, three significant (energy, CO2 and water) balances are established in such a way to verify and tune a reference simulation model of the building zone. [less ▲]

Detailed reference viewed: 31 (1 ULiège)
Full Text
Peer Reviewed
See detailNoWaste: waste heat re-use for greener truck
Bettoja, Federica; Perosino, Andrea; Lemort, Vincent ULiege et al

in Proceedings of 6th Transport Research Arena (2016)

The present paper summarizes the key points of the European NoWaste Project, which aims at developing Rankine cycle systems for integration into long-haul trucks with the aim to convert the waste heat of ... [more ▼]

The present paper summarizes the key points of the European NoWaste Project, which aims at developing Rankine cycle systems for integration into long-haul trucks with the aim to convert the waste heat of the exhaust gases into useful energy usable in mechanical or electrical form. The first part of the paper describes the ORC system architectures defined for two different truck engines: one with EGR and the other one without EGR. For both engines, different cycle configurations and working fluids are compared in terms of energy performance and technical constraints. For both ORC systems, the paper shows the final technical choices made in terms of main components: boiler, condenser, expander and pump. The second part of the paper presents preliminary experimental results carried out on demonstrators of the two ORC systems. The objectives of these tests were to check the performance announced by the components’ manufacturers. Finally, the last part of the paper compares the cost of both systems. [less ▲]

Detailed reference viewed: 70 (14 ULiège)
Full Text
Peer Reviewed
See detailPositive displacement expanders for Organic Rankine Cycle systems
Lemort, Vincent ULiege; Legros, Arnaud

in Macchi, Enio; Astolfi, Marco (Eds.) Organic Rankine Cycle (ORC) Power Systems: Technologies and Applications (2016)

Detailed reference viewed: 64 (11 ULiège)